WO2021139980A1

WO2021139980A1 - Cooling device for a motor vehicle

Info

Publication number: WO2021139980A1
Application number: PCT/EP2020/086406
Authority: WO
Inventors: Serghei Soltoian; Aurore BRIALLART; Thibault DE BOCK
Original assignee: Renault S.A.S; Nissan Motor Co., Ltd.
Priority date: 2020-01-07
Filing date: 2020-12-16
Publication date: 2021-07-15
Also published as: KR20220121882A; FR3105982A1; FR3105982B1; EP4088014A1

Abstract

Cooling device (11) for a motor vehicle (1), characterised in that it comprises: - a first heat exchanger (6) and - an air guide (12) comprising a frame (13) surrounding the first heat exchanger (6), the first heat exchanger (6) comprising: - a body (16) through which an air flow can pass and - a first fastening interface (17) arranged along a first side of the body (16), - a second fastening interface (18) arranged along a second side of the body (16), the second side being opposite to the first side, the first heat exchanger (6) being fastened to the air guide (12) by means of the two fastening interfaces (17, 18).

Description

TITLE: Cooling device for a motor vehicle Technical field of the invention

The invention relates to a cooling device for a motor vehicle. The invention also relates to a motor vehicle comprising such a cooling device. The invention also relates to a method of manufacturing such a cooling device.

State of the prior art

Motor vehicles are equipped with cooling systems making it possible to cool various components of the vehicle, in particular making it possible to cool a combustion engine of the vehicle. A cooling system generally comprises a circuit in which a heat transfer fluid circulates. The heat transfer fluid heats up on contact with the components of the vehicle and cools by passing through a heat exchanger, also called a radiator. The heat exchanger generally comprises a body provided with channels in which the heat transfer fluid circulates. The heat exchanger is positioned so that an air flow passes through it. In particular, the heat exchanger can be positioned at the front of the vehicle so as to receive an air flow when the vehicle is moving forward.

A vehicle can thus comprise a first heat exchanger for cooling oil used to lubricate and cool components of the vehicle, and a second heat exchanger for cooling water or at least a water-based heat transfer fluid. These heat exchangers include interfaces for attachment to a frame of the vehicle. Various pieces of equipment can then be attached to the heat exchangers by means of specific fixing interfaces. In particular, it is known to fix the first heat exchanger on the second heat exchanger, behind the latter. The same air flow therefore crosses successively the second heat exchanger then the first heat exchanger. In addition, an air guide is generally fixed around these two heat exchangers. The air guide makes it possible to channel the air flow so as to force the passage of air through the two heat exchangers. These different fixings require specific fixing interfaces. These fastening interfaces are generally bulky and can limit the efficiency of each of the two heat exchangers. In particular, the fixing interfaces can reduce the useful surface of a heat exchanger and therefore reduce an air flow that can pass through it. In addition, these fixing interfaces generate excess weight and a significant bulk. They can also undergo significant stresses in the event of thermal expansion.

Presentation of the invention

The aim of the invention is to provide a cooling device overcoming the above drawbacks and improving the cooling devices known from the prior art.

More precisely, a first object of the invention is a cooling device making it possible to maximize the flow of air passed through the body of a heat exchanger.

A second object of the invention is a light and space-saving cooling device.

A third object of the invention is a cooling device that is easy to manufacture.

A fourth object of the invention is a solution for fixing a heat exchanger compatible with thermal expansions. Summary of the invention

The invention relates to a cooling device for a motor vehicle comprising:

- a first heat exchanger and - an air guide comprising a frame surrounding the first heat exchanger, the first heat exchanger comprising:

- a body capable of being crossed by an air flow and

- a first fixing interface arranged along a first side of the body,

a second fixing interface arranged along a second side of the body, the second side being opposite to the first side, the first heat exchanger being fixed to the air guide by the two fixing interfaces.

The first attachment interface may include a plastic material overmolded on the first side of the body, and / or the second attachment interface may include a plastic material overmolded on the second side of the body.

The first heat exchanger may include a first header box along the first side of the body and a second header box along the second side of the body, the first attachment interface being molded onto the first header box and / or the second attachment interface. being overmolded on the second manifold.

The cooling device may comprise a housing equipped with a thermostat, an inlet duct and an outlet duct, the cooling device comprising a means for positioning the housing relative to the air guide. The first heat exchanger may comprise an inlet duct and an outlet duct, the inlet duct being positioned in a first slot arranged in a wall of the air guide, and / or the outlet duct being positioned in a second slot arranged in a wall of the air guide.

The cooling device may comprise a first sealing element made of flexible material, in particular rubber or foam, the first sealing element being arranged at the interface between the first slot and the inlet duct, and / or in it may comprise a second sealing element made of flexible material, in particular rubber or foam, the second sealing element being arranged at the interface between the second slot and the outlet duct.

The first heat exchanger may extend generally in a plane, the first heat exchanger being fixed in play to the air guide so as to be able to move parallel to said plane, and / or the first heat exchanger being fixed to the air guide so as to be immobilized perpendicular to said plane.

The air guide can include a central opening and the first heat exchanger can include a width substantially equal to the width of the central opening and a height strictly less than the height of the central opening.

The air guide can comprise a transverse bar delimiting two distinct openings of the air guide, each of the two openings being able to be traversed by an air flow, the two fixing interfaces of the first heat exchanger being fixed to the transverse bar. . The cooling device may include a second heat exchanger extending substantially parallel to the first heat exchanger, the air guide following the contour of the second heat exchanger.

The invention also relates to a motor vehicle comprising a cooling device as defined above.

The invention also relates to a method of manufacturing a cooling device as defined above, the manufacturing method comprising:

a step of positioning the first heat exchanger relative to the air guide, the positioning of the first heat exchanger relative to the air guide being determined by positioning a housing of the first heat exchanger relative to the air guide, the housing being equipped with a thermostat and / or an inlet duct and / or an outlet duct, then

a step of fixing the first heat exchanger to the air guide by means of the two fixing interfaces.

The manufacturing process can then include a step of fixing the air guide to a second heat exchanger.

Presentation of figures

These objects, characteristics and advantages of the present invention will be explained in detail in the following description of a particular embodiment made without limitation in relation to the accompanying figures, among which:

FIG. 1 is a schematic view of a motor vehicle according to one embodiment of the invention. Figure 2 is a perspective and front isometric view of a cooling device according to one embodiment of the invention. Figure 3 is a perspective and rear isometric view of the cooling device.

Figure 4 is a perspective and exploded view of the cooling device.

Figure 5 is a rear view of part of the cooling device.

FIG. 6 is a perspective view of two slots provided in an air guide of the cooling device.

FIG. 7 is a perspective view of a first means for fixing a heat exchanger of the cooling device.

FIG. 8 is a perspective view of a second means for fixing the heat exchanger of the cooling device.

FIG. 9 is a perspective view of a fixing interface for the heat exchanger of the cooling device.

FIG. 10 is a perspective view of a support means integrated into the air guide of the cooling device

FIG. 11 is a perspective view of the support means, the support means being constrained in bending by a support against the heat exchanger of the cooling device.

detailed description

FIG. 1 schematically illustrates a motor vehicle 1 equipped with a cooling system 2 according to one embodiment of the invention. The vehicle 1 can be of any kind. In particular, it may for example be a private vehicle, a utility vehicle, a truck or a bus. The cooling system 2 comprises a first circuit 3 and a second circuit 4, independent of the first circuit. A heat transfer fluid circulates in a closed cycle in each of the two circuits 3 and 4. According to the embodiment described, the heat transfer fluid circulating in the first circuit is oil and the second coolant is water or a water-based coolant. Alternatively, the heat transfer fluids could be different. The first circuit comprises at least one member 5 capable of heating up during operation of the vehicle, a first heat exchanger 6 and a pump 7 capable of circulating the oil in the first circuit. Likewise, the second circuit comprises at least one member 8 capable of heating up during operation of the vehicle, a second heat exchanger 9 and a pump 10 capable of circulating water in the second circuit. The first heat exchanger 6 and the second heat exchanger 9 form part of a cooling device 11 according to one embodiment of the invention.

In this document, the X axis denotes the longitudinal axis of the vehicle 1. When driving forward and in a straight line, the vehicle moves from rear to front in a direction parallel to its longitudinal axis. The X axis is oriented from the front to the rear of the vehicle, that is, in the direction of reverse. The Y axis designates the transverse axis of the vehicle. The Y axis is oriented from left to right, with left and right defined from the point of view of a driver of the vehicle 1. The Z axis is the axis perpendicular to the X axis and the Y axis. The Z axis is a vertical axis when the vehicle is resting on level ground. The Z axis is oriented from bottom to top. The X, Y and Z axes form an orthogonal coordinate system.

FIGS. 2 and 3 respectively illustrate, in front view and in rear view, the cooling device 11 according to one embodiment of the invention. The second heat exchanger 9 is masked in these figures so as to make the first heat exchanger 6 clearly visible. The first heat exchanger 6 and the second heat exchanger 9 both extend parallel to a plane perpendicular to the longitudinal axis X The first heat exchanger 6 is positioned behind the second heat exchanger 9. An air gap can separate the first heat exchanger 6 of the second heat exchanger 9. When the vehicle 1 is moving forward, the air flow generated by its movement first passes through the second heat exchanger 9 then the first heat exchanger 6.

In addition to the two heat exchangers 6 and 9, the cooling device also comprises an air guide 12. The air guide 12 comprises a frame 13 arranged around the first heat exchanger 6 and the second heat exchanger 9. The frame 13 comprises a central opening 14 inside which are housed the first heat exchanger 6 and the second heat exchanger 9. More particularly the air guide 12 has a generally rectangular exterior shape. It extends generally in a plane perpendicular to the longitudinal axis X. The air guide further comprises at least one transverse bar 15 extending parallel to the transverse axis Y. The transverse bar therefore passes through the 'central opening 14 and separates it into at least two secondary openings 14A, 14B. A first secondary opening 14A is arranged above a second secondary opening 14B along the Z axis. The air guide conforms to the shape of the second heat exchanger, that is to say that the second heat exchanger occupies substantially the entire central opening 14. The first heat exchanger 6, of smaller height than the second heat exchanger 9 along the Z axis, occupies the secondary opening 14A. The transverse bar 15 is positioned just below the first heat exchanger 6. As a variant, the first heat exchanger could be positioned at the bottom of the air guide 12 and occupy the secondary opening 14B. According to another variant, the air guide 12 could comprise two transverse bars and the first heat exchanger would then be positioned halfway up the air guide, between these two transverse bars. The air guide delimits the outer contour of the cooling device 11. It also makes it possible to protect the two heat exchangers 6 and 9 laterally. The air guide makes it possible to guide an air flow towards the two heat exchangers by preventing the air to escape to the sides. In other words, it makes it possible to channel the air flow so as to force the passage of air through the two heat exchangers 6 and 9. For this purpose, the air guide comprises walls which extend parallel to the longitudinal axis X. The length of the air guide along the longitudinal axis X may be of the order of magnitude of the length of the superposition of the two heat exchangers 6 and 9 along the longitudinal axis X. The length of the air guide can also be greater than the superposition of the two heat exchangers 6 and 9 along the longitudinal axis X, because it is often intended to guide the air from an air inlet which is at the front of the vehicle . The first radiator or heat exchanger, in our case, is housed in the air guide in order to avoid leaks on the sides after the passage of its bundle, the air guide arriving at the level of the bundle of the second radiator or heat exchanger to be crossed by air. It is not necessary to extend the air guide along the longitudinal axis X substantially beyond the level of the bundle of the second exchanger.

The thickness of the walls constituting the air guide may be of the order of a few millimeters. Thus, the air passage section can be maximized. A compromise can be made at the level of the bar consisting of ribbing it so as to create interstices allowing as much air as possible to pass along the longitudinal axis X. This also makes it possible to lighten the air guide. Advantageously, the air guide can be made of plastic material of the mono or bi-material type. The air guide can be a one-piece element, for example obtained by plastic injection. As a variant, it could for example be made of sheet metal or any other material comprising characteristics of equivalent mass and / or rigidity. The first heat exchanger 6 is also clearly visible in FIG. 4 in which the second heat exchanger 9 is still hidden. The first heat exchanger 6 comprises a body 16 capable of being traversed by an air flow, a first fixing interface 17, a second fixing interface 18, and a housing 19. The housing 19 is equipped with a thermostat 20, an inlet duct 21 and an outlet duct 22.

The body 16 is a part of the heat exchanger intended to be cooled by an air flow. It can be provided with channels in which the oil circulates. The body 16 has a generally rectangular shape extending perpendicularly to the longitudinal axis X. The body 16 therefore comprises four sides, two sides of which extend parallel to the transverse axis Y and two sides extend parallel to the body. axis Z. The dimension of the body 16 in the plane perpendicular to the longitudinal axis X may be substantially equal to the dimension of the secondary opening 14A. In other words, the body 16 occupies substantially the entire width of the opening 14A of the air guide. The body 16 can be equipped with fins and / or a honeycomb structure and / or any other structure making it possible to increase a heat exchange surface with the air circulating along the body 16.

The housing 19 is attached to the body 16 and rigidly fixed thereto. The housing 19 is positioned next to the first fixing interface 17. It may have a generally parallelepipedal shape. The housing 19 contains the thermostat 20, that is to say a valve whose flow of fluid passing through it can be adjusted as a function of a temperature. The thermostat therefore makes it possible to regulate the quantity of oil circulating inside the body 16. Internal conduits to the first heat exchanger therefore make it possible to connect the box 19 to the body 16. The inlet duct 21 extends from the housing 19 substantially parallel to the transverse axis Y. The outlet duct 22 also extends from the housing 19, substantially parallel to the Z axis. The inlet duct and the outlet duct are in the form of a generally cylindrical tube. Alternatively, the orientation of these two ducts could be reversed, i.e. the inlet duct would extend substantially parallel to the Z axis and the outlet duct would extend substantially parallel to the Z axis. transverse axis Y. The inlet duct and the outlet duct therefore preferably extend in directions perpendicular to each other. These directions are both perpendicular to the longitudinal axis X. As a variant, the two conduits 21, 22 could each extend in any other direction.

Body 16 and housing 19 can be made of metal and rigidly secured together. The body 16 and the housing 19 can be generally undeformable compared to a plastic material. In particular the housing 19 comprising the thermostat 20 may be the most rigid part of the first heat exchanger.

The two fixing interfaces 17, 18 connect the first heat exchanger 6 to the air guide 12. In particular, the two fixing interfaces 17, 18 can be fixed to an upper edge of the frame 13 of the air guide 12 and to the air guide 12. transverse bar 15. The first heat exchanger is therefore fixed directly to the air guide 12 by means of its two fixing interfaces 17, 18. In particular, the first heat exchanger 6 is not fixed directly to the second heat exchanger 9. The first heat exchanger 6 and the second heat exchanger 9 are not in contact with each other.

The two fixing interfaces 17, 18 are respectively arranged along two opposite sides of the body. The two opposite sides of the body on which the fixing interfaces 17, 18 are arranged are sides extending parallel to the Z axis. In particular, the heat exchanger may include two manifolds extending parallel to the Z axis on either side. of the body 16. The manifolds are buffer volumes in which the heat transfer fluid can be stored before circulating through the channels arranged in the body 16. The two fixing interfaces 17, 18 can cover these manifolds and extend over the entire height of the body 16. The term “opposite sides” is preferably understood to mean two parallel sides. More preferably, the opposite sides are not adjacent. Preferably, the first heat exchanger is fixed exclusively by the first and second interfaces.

The two fixing interfaces 17, 18 are made of plastic. The use of plastic gives the fixing interfaces a certain flexibility which can be useful to compensate for thermal expansions and / or dispersions associated with the manufacture of elements of the cooling device. Advantageously, the fixing interfaces are overmolded on the two opposite sides of the body, in particular overmolded respectively on the two manifold boxes of the body. As a variant, the fixing interfaces could be in the form of half-shells fixed together, in particular clipped together around the two opposite sides of the body. According to another variant embodiment, the fixing interfaces 17, 18 are produced directly with the manifolds in the sense that they respectively come from the material of one of the manifolds of the first heat exchanger 6, which is then produced by molding of 'a plastic material. In all cases, the fixing interfaces are held firmly to the body 16. As a note, the fixing interfaces do not cover the housing 19. They do not cover the useful surface of the body 16 either, that is to say the surface of the body 16 extending perpendicularly to the longitudinal axis X and intended to receive an air flow. Thus the fixing interfaces do not reduce not the useful surface of the body 16. They do not reduce the useful surface of a body of the second heat exchanger 9 either.

The fixing interfaces 17, 18 can be at least globally identical or symmetrical. They each comprise a first fixing means 23 and a second fixing means 24. The first fixing means 23 is arranged at the top of each fixing interface 17, 18 and it cooperates with the upper edge 25 of the frame 13 of the guide. air 12. The second fixing means 24 is arranged at the bottom of each fixing interface 17, 18 and it cooperates with the transverse bar 15 of the air guide 12. According to the embodiment which is presented the fixing means 23, 24 are produced by holes capable of cooperating with fixing screws 26. As a variant, these fixing means could be produced, for example, with clips.

The second heat exchanger 9, not shown, can also include a body extending perpendicularly to the longitudinal axis and capable of being traversed by an air flow. This body can then extend over the entire surface of the main opening 14. The useful surface of the body of the second heat exchanger, that is to say the surface of the body of the second heat exchanger which receives an air flow. (the area perpendicular to the longitudinal axis X) is larger than the useful area of the body of the first heat exchanger. Thus all of the air flow passing through the body of the first heat exchanger has first passed through the body of the second heat exchanger. On the other hand, part of the air flow passing through the body of the second heat exchanger does not pass through the body of the first heat exchanger. The second heat exchanger 9 can also be attached to the air guide 12. FIG. 5 illustrates in more detail a particular feature of the cooling device, in particular the interface between the housing 19 and the air guide 12. The air guide 12 comprises a first chamber 27 in which the inlet duct is arranged. 21, and a second chamber 28 in which the outlet duct 22. The two chambers are integrated into the frame 13 of the air guide 12, in particular at the level of an upper part of a lateral edge of the frame. In particular, they are arranged in a lateral edge of the air guide facing the first heat exchanger 6. The first chamber 27 comprises walls 29 substantially parallel to the longitudinal axis X. Likewise, the second chamber comprises walls 30 substantially parallel to the longitudinal axis X.

The two chambers 27, 28 are positioned side by side. A wall 31 is common to both the first chamber and the second chamber. The first chamber 27 and the second chamber 28 respectively isolate the inlet duct 21 and the outlet duct 22 of the housing 19. In addition, the walls 29, 30, 31 form ribs and thus participate in the overall rigidity of the guide d. 'air 12.

The air guide includes a first slot 32 through which the inlet duct passes. This slot 32 is arranged in one of the walls 29 forming the first chamber, in particular a wall extending perpendicularly to the axis in which the inlet duct extends. Likewise, the air guide comprises a second slot 33 through which the outlet duct passes. This second slot 33 is arranged in one of the walls 30 forming the second chamber, in particular a wall extending perpendicularly to the axis in which the outlet duct extends. The first slot 32 and the second slot 33 are also clearly visible in FIG. 6. They may have a generally identical shape. The two slots 32, 33 can open towards the rear of the air guide. The two slots may have a generally keyhole shape. They include a narrow portion 34, opening towards the rear, and a wider portion 35 at the bottom of the slot. When the first heat exchanger 6 is fixed to the air guide 12, the inlet duct and the outlet duct are positioned at the bottom of their respective slot, in the wider portions 35.

The sealing device further comprises a first sealing element 36 made of flexible and / or elastic material, arranged at the interface between the first slot and the inlet duct. Likewise, the sealing device comprises a second sealing element 37 made of flexible material, arranged at the interface between the second slot and the outlet duct. The first sealing element and / or the second sealing element can be made, for example, of rubber or foam. They are flexible enough to deform and allow the inlet and outlet conduits to pass along the narrow portions 34 of each slot when assembling the first heat exchanger to the air guide. The sealing elements make it possible to fill a gap existing between the edges of each slot 32, 33 and the respective conduits. They therefore prevent an air flow from escaping through the slots 32, 33. The air flow thus remains concentrated towards the housing 19 and the body 16. Alternatively, the slots 32, 33 could not be. fitted with sealing elements 36, 37 if air leakage through the slits is acceptable.

When the inlet duct 21 is in place in the first slot 32, it can only slightly move parallel to the Z axis thanks to the elasticity of the first sealing element 36. The positioning of the inlet duct 21 in the first slot 32 does not by itself define the position of the first heat exchanger 6 relative to the air guide 12 along the Z axis. The position of the first heat exchanger 6 along the Z axis can be defined by resting the body of the thermostat, in particular on the axis of the screw in the upper left part. Likewise, when the outlet duct 22 is in place in the second slot 33, it can only slightly move parallel to the transverse axis Y thanks to the elasticity of the second sealing element 37. The positioning of the duct outlet 22 in the second slot 33 does not by itself therefore define the position of the first heat exchanger 6 relative to the air guide 12 along the transverse axis Y. The position of the first heat exchanger 6 along the Y axis can be defined by pressing the body of the thermostat. The position along the transverse axis Y can be limited on the other side by the blank of the elastic clip in the upper part of the thermostat. Thus, the two slots 32, 33 do not constitute a means of positioning the housing, but serve for the extraction of the inlet and outlet ducts towards the air chambers external to the air guide. When expansions occur under the effect of high temperatures, relative movements between the heat exchanger and the air guide are possible without generating mechanical stresses in one or other of these elements, thanks to the holes of oblong fasteners for all left and right screw fasteners.

Furthermore, the two slots 32, 33 do not prevent a translational movement of the first heat exchanger 6 relative to the air guide 12 along the longitudinal axis X. The reaction force of the narrow portions 34 on the ducts 21 and 22 generates an increase in the force necessary to engage or disengage the first heat exchanger 6 against the air guide 12. The position of the first heat exchanger with respect to the air guide along the longitudinal axis X is defined by the cooperation of the fixing means 23, 24 with the frame of the air guide and the fixing screws 26.

Figures 7 and 8 illustrate in more detail the interface between the air guide and the fixing means 23, 24. According to the embodiment presented, the fixing means 23, 24 are made by oblong holes 38. The oblong holes 38 have the shape of an oval oriented parallel to the transverse axis Y. They are positioned substantially opposite a circular hole 39 provided in the air guide 12. The use of such oblong holes therefore allows the fixing interfaces 17, 18 to move relative to the air guide parallel to the transverse axis Y. This makes it possible to compensate for a certain dispersion resulting from the manufacture of the components of the cooling device and / or the relative movements linked to the thermal expansion of components of the cooling device. Advantageously, as can be seen in FIG. 8, the height of the oblong holes 38 in the lower part along the Z axis can also be greater than the diameter of the circular holes 39 to similarly allow a relative displacement between the heat exchanger 6 and the air guide 12 along the Z axis. In particular, as is clearly visible in Figure 8, the height along the Z axis of the Y axis oblong hole positioned at the bottom of the fixing interfaces 17 and 18 is greater to the diameter of the circular hole 39 in the air guide. This device makes it possible to absorb manufacturing dispersions and elongations due to thermal expansion phenomena. The first heat exchanger 6 can therefore be fixed to the air guide 12 with a certain clearance parallel to the Y and Z axes. As a note, the thickness and / or the rigidity of the plastic materials forming the air guide (in particular the walls supporting the slots 32, 33) and the fixing interfaces 17, 18 can also give the first heat exchanger a certain mobility with respect to the air guide. The oblong holes are arranged in upper and lower appendages 40 of each attachment interface 17, 18. These appendages may have a generally rectangular shape extending perpendicular to the longitudinal axis X. The upper appendage 40 of the attachment interface. fixing 18, or even also the upper appendix 40 of the fixing interface 17, can be surmounted by a flange 41 able to bear vertically on an edge of the air guide in order to support the weight of the body 16 and to ensure a positioning along the Z axis. Thus, the fixing screws 26 do not support the weight of the body 16 or of the housing 19 but only serve for the longitudinal fixing of the first heat exchanger. In addition, the rim 41 can help position the first heat exchanger 6 relative to the air guide 12 during their assembly.

Advantageously, the fixing screws 26 are screws suitable for soft materials such as plastic. As can be seen in FIG. 9, the fixing screws 26 may include a pointed end and large threads to fit well into the plastic material forming the air guide. The first heat exchanger is therefore fixed to the air guide without a degree of freedom relative to the longitudinal axis X.

Figures 5, 10 and 11 illustrate another feature of the cooling device according to an embodiment of the invention. The air guide further comprises a resilient support means 42 exerting a downwardly oriented force on the housing 19 so that the left side of the air guide serves as a reference for stopping the cooler in its Y-shaped movement, especially to the right. The support means may be in the form of a flexible tongue, or blade, made of the same material as that forming the air guide 12. The support means 42 exerts a force on the housing 19 which contributes to its good resistance against the air guide 12 without, however, preventing any relative movement between the air guide and the first heat exchanger 6. As a variant or in addition, other equivalent support means could be used to generate a stress on the first heat exchanger parallel to the transverse axis Y or parallel to the longitudinal axis X.

For the manufacture of the cooling device 11, it is first of all possible to manufacture an air guide 12. This can for example be manufactured by plastic injection. At the same time, we can manufacture a first heat exchanger heat exchanger and a second heat exchanger. To manufacture the first heat exchanger, the housing 19 can be assembled to the body 16 and then the two side edges of the body 16 can be overmolded to form the two fixing interfaces. As a variant, the two side edges of the body 16 could be previously overmolded to form the two fixing interfaces and then the body 16 can be assembled to the housing 19. Then, the first heat exchanger 6 can be positioned relative to the air guide 12. The first heat exchanger is inserted parallel to the longitudinal axis X in the air guide 12. The correct positioning of the first heat exchanger relative to the air guide is obtained by positioning the housing 19 of the first heat exchanger relative to the guide d 'air. As the housing 19 forms the most rigid part of the first heat exchanger, it is preferable to first fix the position of the housing 19 and then of the body 16 because the body 16 can more easily deform slightly to adjust its position relative to the guide. air 12. The correct positioning of the housing 19 relative to the air guide can be obtained when the inlet ducts 21 and the outlet duct 22 are positioned respectively in the wider portions 35 of the slots 32 and 33. This positioning of the housing 19 can be obtained when pressing in Y on the sides of the thermostat and in Z resting at the bottom of the thermostat, so that this positioning is immobilized while waiting for the screws, by the elastic blade located in the upper part against the body thermostat. It is essential that there is no transmitted force or friction in the conduits, because they are fixed by aluminum - aluminum welding to the housing and their thickness generally does not exceed one millimeter. The presence of the thermostat, a massive piece of aluminum, made it possible to avoid placing the constraints of fixing on the screws with soft materials. Only then can the fixing screws 26 be screwed through the oblong holes 38 of the fixing interfaces 17, 18 and through the holes circulars 39 of the air guide 12, which will have the effect of freezing the position of the first heat exchanger along the longitudinal axis X, but also along the vertical axis Z in the upper part on the left side, or even along the vertical axis Z in the upper part on the right side, being fitted with a force-taking lug so that the screws only work along the longitudinal axis X.

Once the first heat exchanger 6 is fixed to the air guide 12, the air guide 12 can be fixed on the second heat exchanger 9. Advantageously, the second heat exchanger can be assembled to the body by means of filtration, in particular via filter pads in the upper and lower part of this exchanger. The assembly of the cooling device 11 can optionally be completed by fixing other peripherals, for example a fan, against one of the heat exchangers 6, 9 and / or against the air guide 12.

According to an alternative embodiment, the first heat exchanger could not include the box 19. The inlet and outlet conduits would then be arranged directly on one of the two manifold boxes. In this case, it is the manifold carrying the inlet and outlet duct which would position the air guide. The cooling device is preferably attached to the body using filter pads at the top and bottom.

When the cooling device 11 is operating, the air flow generated by the movement of the vehicle 1 successively passes through the first heat exchanger 6 then the second heat exchanger 9, or vice versa. The air cools in a limited way the body 19 which is a massive body in machined aluminum so as to receive all the components making it possible to open and close the circulation of the liquid through the bundle 16. If thermal expansions are produced on all of the coolers 6 and 9, the relative positions of the exchangers thermals 6, 9 and of the air guide can vary without creating mechanical stress in these components. The efficiency of the first heat exchanger is optimal because its fixing interfaces do not reduce its useful surface. The air flow is guided towards the body of each of the heat exchangers which makes it possible to effectively cool the heat transfer fluids circulating inside these bodies.

Claims

1. Cooling device (11) for a motor vehicle (1), characterized in that it comprises: - a first heat exchanger (6) and

- an air guide (12) comprising a frame (13) surrounding the first heat exchanger (6), the first heat exchanger (6) comprising:

- a body (16) capable of being traversed by an air flow and - a first fixing interface (17) arranged along a first side of the body (16),

- a second fixing interface (18) arranged along a second side of the body (16), the second side being opposite to the first side, the first heat exchanger (6) being fixed to the air guide (12) by the two fixing interfaces (17, 18).

2. Cooling device (11) according to the preceding claim, characterized in that the first fixing interface (17) comprises a plastic material overmolded on the first side of the body (16), and / or in that the second interface of attachment (18) comprises a plastic material overmolded on the second side of the body (16).

3. Cooling device (11) according to one of the preceding claims, characterized in that the first heat exchanger

(6) comprises a first header box along the first side of the body (16) and a second header box along the second side of the body (16), the first attachment interface (17) being overmolded on the first header box and / or the second fixing interface (18) being overmolded on the second box collector.

4. Cooling device (11) according to one of the preceding claims, characterized in that it comprises a housing (19) equipped with a thermostat (20), an inlet duct (21) and an outlet duct (22), the cooling device (11) comprising a means for positioning the housing (19) relative to the air guide (12).

5. Cooling device (11) according to one of the preceding claims, characterized in that the first heat exchanger

(6) comprises an inlet duct (21) and an outlet duct (22), the inlet duct (21) being positioned in a first slot (32) arranged in a wall of the air guide (12) , and / or the outlet duct (22) being positioned in a second slot (3) arranged in a wall of the air guide (12).

Cooling device (11) according to the preceding claim, characterized in that it comprises a first sealing element (36) made of flexible material, in particular rubber or foam, the first sealing element (36) being arranged at the interface between the first slot (32) and the inlet duct (21), and / or in that it comprises a second sealing element (37) made of flexible material, in particular rubber or foam, the second sealing element being arranged at the interface between the second slot (33) and the outlet duct (22).

7. Cooling device (11) according to one of the preceding claims, characterized in that the first heat exchanger (6) extends generally in a plane, the first heat exchanger (6) being fixed in play to the guide. air (12) so as to be able to move parallel to said plane, and / or the first exchanger thermal (6) being fixed to the air guide (12) so as to be immobilized perpendicular to said plane.

8. Cooling device (11) according to one of the preceding claims, characterized in that:

- the air guide (12) comprises a central opening (14) and the first heat exchanger (6) comprises a width substantially equal to the width of the central opening (14) and a height strictly less than the height of the 'central opening (14), and / or characterized in that:

- the air guide comprises a transverse bar (15) delimiting two openings (14A, 14B) distinct from the air guide, each of the two openings being able to be traversed by an air flow, the two fixing interfaces ( 17, 18) of the first heat exchanger (6) being fixed to the transverse bar (15).

9. Cooling device (11) according to one of the preceding claims, characterized in that it comprises a second heat exchanger (9) extending substantially parallel to the first heat exchanger (6), the air guide (12) ) following the contour of the second heat exchanger (9).

10. Motor vehicle (1), characterized in that it comprises a cooling device (11) according to one of the preceding claims.

11. A method of manufacturing a cooling device (11) according to one of claims 1 to 9, characterized in that it comprises:

- a step of positioning the first heat exchanger (6) relative to the air guide (12), the positioning of the first heat exchanger (6) relative to the air guide (12) being determined by positioning a housing (19) of the first heat exchanger (6) relative to the air guide (12), the housing (19) being equipped with 'a thermostat (20) and / or an inlet duct (21) and / or an outlet duct (22), then

- a step of fixing the first heat exchanger (6) to the air guide (12) by means of the two fixing interfaces (17, 18).

12. A method of manufacturing a cooling device (11) according to the preceding claim, characterized in that it then comprises a step of fixing the air guide (12) on a second heat exchanger (9).